Nowadays, with the continuous advancement of technology, whether it is an industrial tablet all-in-one computer or an embedded industrial computer, it is more and more widely used. For now, embedded operating systems used internationally can be divided into real-time operating systems and non-real-time operating systems. Two types. For a system with strict time requirements, it can be called a real-time system. An important feature of real-time systems is that they have very strict time requirements. If the real-time system cannot respond to an event within a predetermined time, the system will automatically make an error. Especially in the aerospace and military industries, real-time operating systems must be used.
Beginning in the 1980s, various commercial embedded operating systems appeared on the market. Most of these operating systems were developed for proprietary systems, which gradually evolved into the current various forms of commercial embedded operating systems. A situation where a hundred schools of thought contend. These operating systems include Linux, μC/OS, Windows CE, VxWorks, Palm OS, QNX, and so on.
1, μC/OS
ΜC/OS is a typical real-time operating system. The system began to develop in 1992, and the second version, μC/OSⅡ, is currently popular. Its characteristics can be summarized in the following aspects: open source code, clear and clear code structure, detailed comments, well-organized, good portability, trimming, and solidification, the kernel is preemptive, and it can manage up to 60 tasks. Since Professor Shao Beibei of Tsinghua University translated the book "μC/OS: the Real Time Kernel" by Jean J. Labrosse, a learning boom of μC/OSⅡ has been set off in China, especially in the field of education and research (μC/OS system is in The field of education and research is free). The system is short and succinct, and it is for studying and learning real-time operating systems.
2, Linux
Among all operating systems, Linux is one of the fast-developing and widely-used systems. The various characteristics of Linux itself make it an embedded development. In the first two years of entering the market, the design of embedded Linux has been widely used and has achieved great success. With the maturity of embedded Linux technology, with its features such as customizable systems according to application requirements and support for most hardware platforms, it has moved from the early trial stage to gradually become the mainstream of the embedded market.
According to IDC's report, Linux has become the world's second largest operating system. Another main reason Linux is growing so fast is the cost of the product. In the fierce market competition, it is far from enough to have advanced technology. How to reduce product investment is also an issue that needs to be considered. Free Linux saves a lot of money for manufacturers, especially for companies with weak economic power.
The current new version of the Linux kernel has reached 2.6.xx.
3, VxWorks
VxWorks is an operating system software specially designed and developed by Wind River (Wind River) for real-time embedded systems. It provides programmers with efficient real-time task scheduling, interrupt management, real-time system resources and real-time inter-task communication. Application programmers can put as much energy as possible on the application itself, without having to care about the management of system resources. The system is mainly used in single-board computers, data networks (Ethernet switches, routers) and communications. The company has been acquired by Intel.
4, Windows CE
Windows CE is a product of Microsoft Corporation. It is a multi-threaded, full-priority, multi-tasking operating system designed for platforms with limited resources as a whole. Windows CE adopts a modular design and is customized from handheld computers to dedicated industrial control electronic equipment. The basic kernel of this operating system requires at least 200 KB of ROM memory. From game consoles to today, most high-priced handheld computers have adopted Windows CE as the operating system. The disadvantage is that the system software is too expensive, which affects the cost control of the entire product.
5, QNX
QNX is a real-time operating system, developed by Canada QNX Software Systems Co., Ltd., widely used in automation, control, robotics, telecommunications, data communications, aerospace, computer network systems, medical equipment, transportation, security and defense systems, Mission-critical applications such as POS machines and retail machines. In the late 1990s, the QNX system was also widely used in the rapidly growing Internet terminal equipment, information appliances, and handheld computers.
6, Palm OS
Palm OS is a 32-bit embedded operating system for handheld computers. This system was developed by the PalmComputing Department of 3Com (Palm Computing has now become an independent company). It runs on a preemptive multitasking kernel. The user interface allows only one application to be opened at the same time, combined with the synchronization software Hotsync The information on the handheld computer and the PC can be synchronized, and the functions of the desktop computer can be extended to the palm of the hand. Compared with other embedded operating systems, Palm OS has greater flexibility and mobility, and is a very popular handheld operating system.
